Dodoo, 26, started his career with Leicester City and was a team-mate of Rovers manager Richie Wellens during his time at the King Power Stadium.
Rovers entered the free agent market following a fraught deadline-day which saw them miss out on the signing of Sunderland's Aiden O'Brien and be beaten by Rotherham United in their quest to sign another Black Cats forward in Will Grigg.
Doncaster thought they had completed a deal to sign O'Brien, but an administrative error at Sunderland's end meant the paperwork was not submitted in time to complete the deal. Rovers' appeal to the Football League was rejected.
Dodoo left the Foxes to join Scottish giants Rangers in 2016, and went on to make 24 appearances during his time at Ibrox and also spent time on loan at Charlton Athletic and Blackpool respectively.
He has spent the past two seasons in League One with Bolton Wanderers and Wigan Athletic and scored for both clubs against Rovers in each of his outings at the Keepmoat Stadium.
Dodoo hit four goals in 20 appearances for the Latics in the second half of last term, having netted the same tally of goals during a season at Wanderers in the curtailed 2019-20 campaign.
Dodoo could make his Rovers debut in the Papa John’s Trophy tie at home to Rotherham United on Tuesday night.
On linking up once again with Wellens, the Ghana-born striker, who represented England at under-18 level, said: “I was at Leicester with the manager so we know each other quite well. When the opportunity came for me to join here, things happened quite quickly.
“I’ve always admired the way Doncaster Rovers play. I spoke to the manager and the club has ambition so I’m happy to be part of it.
“The manager wants to play football, he wants to win. He wants to make sure the club do good things, so the ambition of the club and the style of play is what brought me here.”